Distortion usually occurs to an image obtained by performing an image obtaining operation, such as photographing or scanning, on a stereoscopic object. Take a document scanning as an example, distortion, such as perspective transformation and tensile deformation, exists in a scanned image regardless of a traditional flat panel scanner or an advanced curved surface scanner. In addition, take a product logo identification application for an example, there is distortion in an image obtained by photographing a logo on a product such as a beverage bottle, and thus accuracy of identification is affected.
Therefore, to remove distortion, enrich document edition, and improve accuracy of content identification, it is important to obtain an accurate boundary of an image of a document or a logo. In this context, various boundary tracing technologies, for example a dynamic planning technology, have been researched and used widely.